Shimano J04C Metal Pads

Finally, the J04C metal pads arrived. I was considering sanding the rotors with fine grit paper as some advised but looking at them under a magnifying glass the rotor surface area appeared good. I decided the fewer variables changed for the next test run the better. I simply changed out the stock fiber J02A pads with the metal J04C pads. Side by side, the metal pad is not only a more thermally conductive braking surface but also a much beefier pad including an additional silver metal plate that appears designed to conduct heat outward to the fins where the air flows.
20150510_133315It was also good to see that Shimano made them backwards compatible with the F03C pads I had been running on my Santa Cruz Tallboy XTR brakes. I am not certain if the F03C is forwards compatible with the BR-RS785 Road Disc. Here is the compatability table from the back of the packaging.

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